Journal of Entomology and Zoology Studies 2015; 3(5): 374-378
E-ISSN: 2320-7078
P-ISSN: 2349-6800
JEZS 2015; 3(5): 374-378
© 2015 JEZS
Received: 09-08-2015
Accepted: 11-09-2015
Inam Shah
Department of Entomology, the
University of Agriculture,
Peshawar-Pakistan
Maqsood Shah
Department of Entomology, the
University of Agriculture,
Peshawar-Pakistan
Ashraf Khan
Department of Entomology, the
University of Agriculture,
Peshawar-Pakistan
Amjad Usman
Department of Entomology, the
University of Agriculture,
Peshawar-Pakistan
Response of insect pollinators to different
cucumber, Cucumis sativus L. (Cucurbitales:
Cucurbitaceae) varieties and their impact on yield
Inam Shah, Maqsood Shah, Ashraf Khan, Amjad Usman
Abstract
The vast majority of cucurbits tend to be monoecious, therefore pollination is very important element
with regard to strengthening their particular yield. Field experiment was conducted at New
Developmental Farm of the University of Agriculture, Peshawar during the year 2014 to investigate the
population density of insect pollinators on four different varieties (Peshawar Local, Beta Alpha, Market
More and Moon Star (hybrid)) of cucumber and also to evaluate their impact on the yield of cucumber.
The experiment was laid down in RCBD with four different varieties as treatments. Experimental field
was divided into two portions i.e totally Covered (with nylon cloth net) to the entrance of insect
pollinators and Uncovered. The results regarding mean population of pollinators showed the highest
population of honey bees (1.21/plot) among all pollinators and varieties while population of carpenter
bees was recorded to be the lowest (0.03/plot). Population density of pollinators was observed to be
highest during morning and evening times. Uncovered plots yielded significantly higher than covered
plots in all the comparative treatments. The uncovered and covered Peshawar Local produced
21863kgha-1 and 9869 kgha-1, Beta Alpha 20156kgha-1 and 7650kgha-1, Market More 21543kgha-1 and
9748kgha-1 and Moon Star 24619kgha-1 and 11557kgha-1, respectively, throughout the reproductive
season of cucumber crop. Cucumber crop requires insect pollination as an additional input in enhancing
the yield.
Keywords: Pollination, Cucumber, Honey bees, Carpenter bees
Correspondence
Inam Shah
Department of Entomology, the
University of Agriculture,
Peshawar-Pakistan
1. Introduction
Cucumber (Cucumis sativus L.) commonly known as “khira” belongs to Asia and Africa. It
has been used for 3000 years. Today cucumbers are grown worldwide for salad and pickling.
The fruit is commonly harvested while still green. They are used as raw, cooked or pickled
cucumbers. Fresh cucumber is a source of vitamin C, thiamine, niacin, iron, phosphorus
calcium and dietary fiber [1].
Cucumber is a usually monoecious vegetable, where male and female flowers are present on
the same plant. Male flowers are come about in clusters together with each flower using
slender stem and housing three stamens. Female flowers occur singly and so are
distinguishable by actual large ovary for the flower base. This ovary has several chambers,
several series of ovules and it is connected to a short thick style together with three stigma
lobes. Plants have yellow, wrinkled petals, both flowers produce nectar that attracts insect
pollinators. The female flowers produce higher volume of nectar as compared to male flowers,
but sugar concentration is larger in male flowers of cucumber. Cucumber pollen grains are
sticky and suitable to pollination by bees as compared to wind. The stigma is receptive during
the day but more receptive in early morning [2].
Permanently for fruit setting the pollinators play an essential part in cross pollination. Wind
and insects are the main agents of the pollen transfer in cross pollination. Plants are referred to
as self-pollinated when the percentage associated with cross pollination is usually below 4% in
addition to being cross pollinated can be leading. For cucurbit plants this is almost true [3].
Mostly honeybees visit maximum number of flowers for getting nectar. The dusted pollinators
with pollen grains drops on the stigma causing gynoecious fertilization [4].
Cucurbits like cucumber, melons, pumpkin and squash are cross pollinated crops. They need
insect pollinators, especially honey bees for pollination and proper fruit set. In case of poor
pollination, deformed and small sized fruit are produced. Prosperous pollination regarding
several cucurbits demands approximately twenty bees visit for every flower [5].
~ 374 ~ Journal of Entomology and Zoology Studies
In general, fluctuation in foraging activity occurs and same
crop in the same region is impacted by race, colony strength,
food resource, month and the time of the day. Pollinators are
very crucial to agro-ecosystem as 75% of the important crop
species of the world depends on them for fruit or seed set [6].
2. Materials and Methods
The experiment was conducted at New Developmental Farm
of The University of Agriculture Peshawar-Pakistan during
March-August 2014. Field was divided in two main plots with
a distance of 2m (buffer zone) between them. Size for each sub
plot was kept 4×4m2. Each main plot was further subdivided
into subplots to receive four treatments (four varieties) with
three replications. Four different varieties were V1 (Peshawar
Local), V2 (Beta Alpha), V3 (Market More) and V4 (Moon
Star (hybrid)). The experiment was conducted in factorial RCB
split plot design. Row-to-row distance and plant-to-plant
distance was maintained as 1 meter and 30 cm respectively.
Data regarding visits of insect pollinators was initiated after
appearance of flowers and was recorded twice in a week.
Common agricultural practices were used throughout the
research studies.
Nylon cloth was used to cover the sub plots before initiation of
flowering to deny access to pollinators except air and
sunshine. In the uncovered portion, all the sub plots were kept
open to all kind of pollinators to investigate the population
dynamics of insect pollinators and their foraging timings on
four different varieties of cucumber.
2.1. Statistical Analysis
The data recorded for each parameter was analyzed
statistically by using Statistix 8.1 Software and means were
separated by using Fisher Protected Least Significance
Difference Test at
5% level of significance [7].
2.2. Data Collection
2.2.1 Population dynamics and foraging timings of
pollinators
The population of insect pollinators was recorded by observing
three randomly selected plants in each experimental unit
during three different timings of the day i.e. morning (7-9am),
mid-day (12-2pm) and evening (4-6pm). Observation time for
each plant was three minutes. The data was recorded twice in a
week.
2.3. Yield
Data regarding yield of cucumber was recorded after flowering
till the end of fruiting season of cucumber. The ripe cucumbers
of different varieties were separately picked from covered and
un-covered treatments once a week and were weighed. Yield
was converted to kg/ha.
3. Results
Table 1 showed the mean population of honey bees on four
different varieties of cucumber. Highest mean population (1.21
bees/ plot) of honey bees was recorded visiting Peshawar
Local and lower (0.68 bees/ plot) on Moon star. The highest
bees population of honey bees was non significantly followed
by the population on Market More (0.98 bees/ plot) and then
(0.90 bees/ plot) on Beta Alpha. Statistical analysis of the
population density of honey bees regarding three different
timings showed no significant difference. However, highest
bees (1.03 bees/ plot) were observed during evening time and
lowest population (0.78 bees/ plot) was seen in the afternoon.
The honey bees noted during morning time were 1.02 bees/
plot. The table further revealed that significantly higher
population (1.51 bees/ plot) was recorded as a result of the
interaction of varieties, different timing and weekly time
intervals in week 7. This population was not significantly
different from the populations noted during week 1(1.07 bees/
plot), week 2 (1.13 bees/ plot) and week 6 (1.14 bees/ plot).
The lowest population recorded was 0.51 bees/ plot in week
11, followed by week 10 (0.64 bees/ plot), week 8 (0.82 bees/
plot), week 4 (0.82 bees/ plot), week 9 (0.85 bees/ plot), week
3 (0.90 bees/ plot) and week 5 (0.96 bees/ plot).
Table 1: Mean population of honey bees on four different verities of cucumber at three different timings from May to August, 2014.
Treatments
Varieties (v)
Peshawar local
Beta Alpha
Market More
Moon Star
Timings (t)
Morning
Afternoon
Evening
Peshawar local
Beta Alpha
Market More
Moon Star
Morning
Afternoon
Evening
Morning
Afternoon
Evening
Morning
Afternoon
Evening
Morning
Afternoon
Evening
Mean
Lsd for varieties =
Lsd for timings
=
Lsd for intervals =
1
2
3
4
1.17
1.00
1.06
1.06
1.67
1.00
0.78
1.06
1.17
0.72
1.06
0.67
0.94
0.67
1.28
0.39
1.29
0.96
0.96
1.25
1.17
0.96
0.88
0.92
0.92
0.83
0.71
0.92
2.00
1.83
1.17
1.17
1.00
0.83
0.50
0.67
1.17
1.33
1.17
0.67
1.13ab
1.83
0.33
1.33
0.17
1.67
0.33
0.50
1.33
1.33
1.00
0.33
0.67
0.90bd
1.00
0.67
1.17
0.67
0.33
1.00
1.50
1.50
0.83
0.17
0.33
0.67
0.82bd
1.67
0.67
1.17
0.83
1.50
0.67
1.17
0.67
1.33
1.50
1.00
0.67
1.07ac
0.28
024
0.47
Intervals (i) weeks
5
6
7
vxi
1.22
1.28
2.06
1.11
1.61
1.67
0.67
1.28
1.06
0.83
0.39
1.28
txi
1.08
1.83
1.21
0.83
0.46
0.54
0.96
1.13
2.79
vxtxi
1.17
1.33
1.00
1.33
1.00
0.50
1.17
1.50
4.67
1.50
2.33
1.33
1.00
0.50
0.67
0.83
2.00
3.00
0.67
2.83
1.33
0.33
0.33
0.33
1.00
0.67
1.50
1.00
0.83
1.17
0.67
0.00
0.67
0.83
0.33
2.00
0.96bd 1.14ab 1.51a
~ 375 ~ 8
9
10
11
Mean
0.94
0.83
1.00
0.50
1.33
0.56
1.00
0.50
0.83
0.44
0.89
0.39
0.67
0.33
0.67
0.44
1.21 a
0.90 bc
0.98 ab
0.68 c
0.50
1.08
0.88
1.04
0.67
0.83
0.58
0.71
0.63
0.67
0.58
0.33
0.83
1.17
0.83
0.67
1.00
0.83
0.17
1.50
1.33
0.33
0.67
0.50
0.82bd
1.67
0.83
1.50
1.00
0.33
0.33
1.17
1.17
0.67
0.33
0.33
0.83
0.85bd
0.50
1.17
0.83
0.00
0.83
0.50
1.17
0.67
0.83
0.67
0.17
0.33
0.64cd
0.67
1.00
0.33
0.00
0.67
0.33
0.67
0.67
0.67
1.33
0.00
0.00
0.51d
1.02 a
0.78 a
1.03 a
vxt
1.24
0.95
1.42
0.88
0.86
0.97
1.06
0.83
1.03
0.88
0.48
0.68
Journal of Entomology and Zoology Studies
The results in table 2 indicated no significant difference among
the overall mean population of butterflies on four different
varieties of cucumber crop. The maximum population (0.30
butterflies/ plot) was recorded on Peshawar Local and Market
More, respectively, while minimum population was recorded
(0.18 butterflies/ plot) on variety Beta Alpha. The highest
population was followed by Moon Star which was 0.27
butterflies/ plot. The mean population of butterflies regarding
three different timings was recorded as 0.29 butterflies/ plot at
morning, 0.24 butterflies/ plot at afternoon and 0.26
butterflies/plot at evening. Highest population was noticed
during morning time while lowest was observed in afternoon.
Statistically there was no significant difference among the
recorded population of butterflies in three different timings.
Furthermore the results revealed no significant difference for
the interaction of varieties, timings and weekly time intervals.
However, the highest population (0.35 butterflies/ plot) was
recorded in week 9 while the lowest population was recorded
as 0.14 butterflies/ plot during week 11.
Table 2: Mean population of butterflies on four different verities of cucumber at three different timings from May to August, 2014.
Treatments
Varieties (v)
Peshawar local
Beta Alpha
Market More
Moon Star
Timings (t)
Morning
Afternoon
Evening
Peshawar local
Beta Alpha
Market More
Moon Star
Morning
Afternoon
Evening
Morning
Afternoon
Evening
Morning
Afternoon
Evening
Morning
Afternoon
Evening
Mean
Lsd for varieties =
Lsd for timings =
Lsd for intervals =
1
2
3
4
0.61
0.28
0.22
0.22
0.22
0.28
0.39
0.33
0.28
0.39
0.00
0.28
0.33
0.06
0.28
0.17
0.29
0.33
0.38
0.42
0.25
0.25
0.33
0.08
0.29
0.25
0.21
0.17
0.33
0.83
0.67
0.33
0.00
0.50
0.33
0.33
0.00
0.17
0.17
0.33
0.33 a
0.00
0.17
0.50
0.33
0.33
0.17
0.83
0.17
0.17
0.50
0.33
0.17
0.31 a
0.00
0.33
0.50
0.67
0.00
0.50
0.00
0.00
0.00
0.67
0.00
0.17
0.24 a
0.33
0.50
0.17
0.00
0.00
0.17
0.50
0.17
0.17
0.17
0.17
0.17
0.21 a
Intervals (i) weeks
5
6
7
vxi
0.39
0.33
0.33
0.33
0.11
0.06
0.44
0.17
0.33
0.06
0.61
0.44
txi
0.08
0.46
0.29
0.42
0.13
0.21
0.42
0.33
0.38
vxtxi
0.00
0.33
0.67
0.50
0.33
0.33
0.67
0.33
0.00
0.17
0.00
0.00
0.50
0.17
0.17
0.33
0.17
0.00
0.17
0.33
0.17
0.67
0.00
0.17
0.50
0.17
0.67
0.00
1.17
0.33
0.00
0.00
0.17
0.17
0.67
0.83
0.31 a 0.31 a 0.29a
8
9
10
11
Mean
0.39
0.06
0.33
0.22
0.22
0.22
0.72
0.22
0.22
0.11
0.22
0.17
0.00
0.11
0.22
0.22
0.30 a
0.18 a
0.30 a
0.27 a
0.29
0.29
0.17
0.29
0.42
0.33
0.21
0.17
0.17
0.25
0.17
0.00
0.33
0.83
0.00
0.17
0.00
0.00
0.50
0.17
0.33
0.17
0.17
0.33
0.25 a
0.00
0.50
0.17
0.33
0.00
0.33
0.67
0.83
0.67
0.17
0.33
0.17
0.35 a
0.17
0.17
0.33
0.17
0.17
0.00
0.17
0.33
0.17
0.33
0.00
0.17
0.18 a
0.00
0.00
0.00
0.00
0.33
0.00
0.33
0.33
0.00
0.67
0.00
0.00
0.14a
0.29 a
0.24 a
0.26 a
vxt
0.20
0.41
0.30
0.20
0.15
0.20
0.36
0.29
0.26
0.39
0.12
0.29
0.13
0.12
0.2
The results regarding the population of carpenter bees on four
different varieties of cucumber crop is shown in table 3. The
mean population of carpenter bees was recorded as 0.05, 0.06
bees/plot on Beta Alpha, 0.03 bees/plot on Market More and
variety Moon Star. Statistically non significant higher
population was recorded on variety Beta Alpha which was
0.06 bees/ plot while lower mean population was observed as
0.03 bees/ plot on variety Market More and Moon Star,
respectively. The higher population was followed by 0.05
bees/plot on Peshawar Local. Statistical analysis showed no
significant difference among the population of carpenter bees
on four different varieties.
Statistically significant higher mean population (0.08 bees/
plot) of carpenter bees regarding three different timings of the
observation was recorded at morning, followed by 0.03 bees/
plot at afternoon and lower (0.02 bees/ plot) at evening. The
table also indicated the effect on visiting behavior of carpenter
bees by the interaction of varieties, different timings in a day
and weekly intervals in the whole flowering season. The
results in the table 4.3 indicated significantly highest
population of 0.17 bees/ plot during week 4 and was not
significantly different from the population recorded during
week 2 (0.10 bees/ plot) while no bees (0.00 bees/ plot) were
observed to visit the crop in week 5,6,7,8 and 11 respectively,
during the whole fruit set flowering season of cucumber crop.
Table 3: Mean population of carpenter bees on four different verities of cucumber at three different timings from May to Aug, 2014.
Treatments
Varieties (v)
Peshawar local
Beta Alpha
Market More
Moon Star
Timings (t)
Morning
Afternoon
Evening
1
2
3
4
0.00
0.06
0.00
0.00
0.11
0.17
0.06
0.06
0.06
0.00
0.11
0.06
0.28
0.22
0.00
0.17
0.00
0.04
0.00
0.13
0.13
0.04
0.17
0.00
0.00
0.33
0.13
0.04
Intervals (i) weeks
5
6
7
vxi
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
txi
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
~ 376 ~ 8
9
10
11
Mean
0.00
0.00
0.00
0.00
0.06
0.17
0.11
0.00
0.06
0.00
0.06
0.00
0.00
0.00
0.00
0.00
0.05 a
0.06 a
0.03 a
0.03 a
0.00
0.00
0.00
0.17
0.00
0.08
0.04
0.04
0.00
0.00
0.00
0.00
0.08 a
0.03 b
0.02 b
Journal of Entomology and Zoology Studies
Peshawar local
Beta Alpha
Market More
Moon Star
Morning
Afternoon
Evening
Morning
Afternoon
Evening
Morning
Afternoon
Evening
Morning
Afternoon
Evening
Mean
Lsd for varieties=0.04
Lsd for timings=0.04
Lsd for intervals=0.07
0.00
0.00
0.00
0.00
0.17
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.01 cd
0.33
0.00
0.00
0.17
0.33
0.00
0.00
0.17
0.00
0.00
0.00
0.17
0.10ab
0.17
0.00
0.00
0.00
0.00
0.00
0.33
0.00
0.00
0.17
0.00
0.00
0.06 bd
0.33
0.50
0.00
0.50
0.00
0.17
0.00
0.00
0.00
0.50
0.00
0.00
0.17 a
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00 d
The yield obtained from all the four varieties of cucumber
during the whole cropping season is presented in table 4. The
results indicated that the yield obtained from uncovered plots
was significantly higher than the yield resulted from covered
plots for all the four varieties comparatively. The uncovered
and covered plots of Peshawar Local produced 21863 kgha-1
and 9869 kgha-1, Beta Alpha 20156 kgha-1 and 7650 kgha-1,
Market More 21543 kgha-1 and 9748 kgha-1 and Moon Star
24619 kgha-1 and 11557 kgha-1, respectively, throughout the
reproductive season of cucumber crop. The mean yield for all
the varieties from uncovered plot was 22045.25 kgha-1 and
covered plots was 9706 kgha-1. Substantial yield difference
was recorded relating to the uncovered and covered plots.
Table 4: Effect of pollinators on the yield in kgha-1 of four different
varieties of cucumber
Varieties
Peshawar Local
Beta Alpha
Market More
Moon Star
Mean
Treatments
Uncovered
Covered
21863a
9869b
20156a
7650b
21543a
9748b
24619a
11557b
22045.25 a
9706 b
4. Discussion
Part of pollinators inside of raising the yield as well as quality
of crops is really a significantly explored subject. Pollination
can be an essential move within the sexual production
associated with cucurbits and also Angiosperms. Almost all
angiosperm depends upon insects as well as various other
animals as compared to wind, regarding move of pollen among
particular crops. Insect pollinators in-turn help by means of get
floral belongings including nectar as well as pollen [8]. Our
results indicated that only honey bees showed the varietal
preference among all the pollinators and showed their
abundance mostly in evening time because of ideal
temperature. But the other pollinators showed no varietal
preference throughout the reproductive period of cucumber
crop. Nicodemo et al., (2009) [9] stated that large and
monoecious flowers of cucurbits produce plenty of nectar and
pollen and attract a wide array of insect visitors, particularly
honey bees. The population of carpenter bees has been
recorded to be the lowest among the three pollinators.
Although carpenter bees have been recorded as efficient
pollinators of many crops but we could not found their
abundance as compared to honey bees and butterflies. This
may be due to absence of their colonies and climatic
conditions. The population of pollinators tended to increase
from the start of flowering and reached to its peak during the
vxtxi
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00 d
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00d
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00 d
0.17
0.00
0.00
0.17
0.00
0.33
0.33
0.00
0.00
0.00
0.00
0.00
0.08 bc
0.00
0.17
0.00
0.00
0.00
0.00
0.17
0.00
0.00
0.00
0.00
0.00
0.03 bd
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00d
vxt
0.09
0.06
0.00
0.08
0.05
0.05
0.08
0.02
0.00
0.06
0.00
0.02
mid of season i.e. week 7 because of the flowering period of
crop was on peak at this stage and then started to decrease due
to maturity of crop and finished season of flowering. Honey
bees population was recorded the highest population among all
the pollinators. Our findings are in accordance to results of
Shultz JI [10] who demonstrated that 95% of honey bees are
involved in visiting bitter gourd and cucumber which implies
that cucurbits are good forage for bees. It was also confirmed
by Kieth M [11] who assured that over 50% of pollination is
affected by hymenopteran insects, while 20%, 15% and 10%
of pollination is done by dipterans, beetles and lepidopteran
insects, respectively, while the remaining 5% is done by
insects belonging to other insect orders.
Yield data showed that more yield was obtained from
uncovered plot. The results of yield in table 4.5 clearly
indicated that the actual yield is usually frequently and
considerably larger inside insect pollinated plots through the
entire growing time. Fruit set likewise taken place inside
covered plots. This can be because of pollination was
accomplished by wind. The higher yield may be due to
maximum visits of pollinators (bees along with butterflies)
towards treatment where the insect had open access while the
treatments with no access to pollinators resulted in lower
observations regarding yield. Sneep FD [12] noted that natural
pollination along with manually enhanced pollination as a
combined method provided greater yield. This signifies that
setting of fruit set may also be done by flowers pollinated by
wind. Our findings are in conformity with Laberge HM [13],
who recorded 60 percent increase in yield of cucumber
achieved by utilization of pollinators. Our results are also in
accordance with that of Parker FD [14] who observed in plants
covered together with pollinators generated 25 % more yield in
comparison to other crops which were caged without
pollinators.
5. Conclusion
On the basis of results we concluded from this research that
honey bees are the most frequent visitors of cucumber crop as
compared to other pollinators. Most of pollinators were
recorded in the time of evening and morning due to moderate
temperature but we could not clearly found any varietal
preference among pollinators accept honey bees which showed
preference on variety Peshawar local. Significant difference
was recorded between yields obtained from covered and
uncovered plots. The uncovered plot yielded significantly
higher than the covered plot because of insect pollination.
6. Recommendations
Cucumber crop requires bee pollination as an additional input
in enhancing the yield. Future research regarding developing
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conservation strategy for both most efficient as well as less
efficient pollinators should be conducted. The growers should
keep the bee colonies near the cucumber field as soon as first
fruit producing flower appears to get higher yield.
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